Sunday, June 11, 2017

SpaceX Scores! Re-Used Dragon Docks with ISS

View from ISS: Robotic arm guides the captured Dragon cargo ship to its docking port. (NASA TV)

It has been a dream of the folks at SpaceX to begin launching re-used spacecraft, with the goal to reduce costs of space transportation. Well they can check off a major milestone now, because on June 3rd, they launched the first refitted Dragon cargo space capsule on board a Falcon 9 rocket. Days later, the Dragon caught up to the ISS and astronauts Peggy Whitson and Jack Fischer used the SSRMS (Space Station Remote Manipulator System) robotic arm to grapple the craft and move it to dock at the U.S. Harmony module.

Current locations of docked spacecraft at the International Space Station. (NASA)
 
The Dragon spacecraft used on this mission (CRS-11) was previously used on mission CRS-4. After returning safely to Earth, it was unloaded, inspected, cleaned, and repaired with some new parts to keep it in operable condition. The only spacecraft to have done this sort of thing before, was the Space Shuttle, last docked at the ISS in 2011. This is the second time SpaceX has reached a re-usability objective - the first was in March when a refurbished Falcon 9 first stage successfully delivered a satellite to orbit and then landed again. Although the Falcon 9 used in this mission has not flown before, it did land safely at LC-13 at Cape Canaveral, and will now be refurbished for a future flight.
Falcon-9 rocket safely standing after an upright landing on pad LC-13. (SpaceX)

The ISS crew will take their time removing science equipment and space parts from the Dragon. It will stay docked until July 2nd. This week will keep them quite busy, as the schedule sees two spacecraft events: the undocking of Russian Progress 66 from the station, and the arrival of a new Russian ship, the Progress 67.

Sunday, June 4, 2017

ISS: Cargo and Crew Transfers Underway

Soyuz MS-03 undocks from the International Space Station. A Progress Supply ship is docked in the background. (Credit: NASA)

On June 2, Soyuz ship MS-03 departed for a return trip to Earth. Rather than the usual three crewmembers, this trip only included two: Oleg Novitskiy (Roscosmos) and Thomas Pesquet (ESA). 
Before the departure, a Change of Command ceremony took place.
Peggy Whitson turns over command of the station to Fyodor Yurchikhin. (Credit: NASA TV)

On June 1st, Expedition 51 officially ended when astronaut Peggy Whitson gave command to cosmonaut Fyodor Yurchikhin. With the ceremony completed, the Expedition 52 period did not officially begin until Novitskiy and Pesquet departed for Earth. The two had 196 days in space before leaving on Friday. Crew reinforcements for Expedition 52 will arrive in July.
From L-R: Novistkiy, Whitson, Pesquet. (NASA)
 
 
Computer simulation of Soyuz module separations during re-entry process. The crew is located in the center module, which has the heat shield. The service module and crew docking module burn up during re-entry.
 
Touchdown! Soyuz MS-03 safely lands after firing landing thrusters activate during the final few moments of descent. Landing took place in Kazakhstan.

Meanwhile, there is a resupply mission ending and another one beginning. SpaceX was due to launch a special resupply mission on Friday, but had to postpone for a day because of lightning concerns at the launch site. This mission (CRS-11) would feature the first use of a reusable Dragon cargo ship. Ship number C-106 was last used on mission CRS-4 in September of 2014.



Falcon-9 rocket lifts off from LC-39A at Kennedy Space Center, FL. (Credit: SpaceX)

Actual launch of mission CRS-11 took place Saturday June 3. The Falcon 9 rocket took off flawlessly and after ten minutes separated from the Dragon spacecraft, which continued its flight into orbit. The rocket itself however, descended by parachute and engine power to land vertically back at Kennedy on pad LC-13. With a safe landing, the rocket can be refurbished and prepared to be reused on another future flight.

Cygnus resupply spacecraft. (NASA)
 
While Dragon makes its way to the ISS, another ship is leaving. Early Sunday morning, astronauts Jack Fischer and Peggy Whitson used the station's CanadArm robotic arm to pull the undocked Cygnus spacecraft OA-7 (Named John H. Glenn) from its berth and release it. This move comes a month earlier than scheduled, in an effort to reduce the future workload for the crew. The Cygnus will now move away from the station, and spend a week doing experiments under control from ground flight engineers. The John H. Glenn will deploy several small satellites on Thursday, and after experiments are completed, the craft will de-orbit and burn up over the Pacific Ocean on June 11.

 

Sunday, May 28, 2017

Equipment Failure on ISS Triggers Unplanned EVA

Astronaut Peggy Whitson making repairs to the EXT-1.
 
It doesn't happen often on the ISS, but when a critical electrical command component breaks down, it's great to know there's a backup system in place. In this case, on May 20 the EXT-1 MDM electrical command controller went down. It controlled external US segment systems, which includes things like the Mobile Transporter (MT),  Secondary Electrical Power System (SEPS), Passive Thermal Control System (PTCS), and a couple of Truss rotary joints. When the system failed, the EXT-2 took over right away so there was no degradation of systems. However, if THAT item were to fail, NASA would have lost control over the facing direction of the solar radiators and several other critical station systems along the Truss.
Astronaut Jack Fischer moves along the outside of a module.
 
Immediately the decision was made to go outside and replace the broken equipment. Using components stored aboard the station for such a situation, a new EXT-1 was assembled and tested. Then on May 23, astronauts Peggy Whitson (Commander of Expedition 51) and Jack Fischer made a short spacewalk of over two hours. The mission event was a success, and systems are back to normal.
Record holders for EVAs.
 
This EVA brings Peggy Whitson into the top three record holders for time spent on spacewalks. Currently, the Russians hold the lead.
You can read more details of the operation at NASA SpaceFlight.com: https://www.nasaspaceflight.com/2017/05/spacewalkers-unplanned-eva-replace-failed-ext-1-mdm/

Sunday, May 14, 2017

200th EVA for ISS

US Astronaut Jack Fisher prepares to enter the airlock and go for a walk.
 
Although designated US-42, the spacewalk on Friday by two US astronauts was also the 200th spacewalk for the construction and maintenance of the International Space Station. Astronauts Peggy Whitson (NASA, Commander of Expedition 51) and Jack FIsher (NASA, Exp. 51 flight engineer, on his first mission in space) conducted a four hour spacewalk that was shortened due to problems with battery power in one of the suits.

During their EVA, they accomplished quite a bit of work. They replaced an avionics box supplying electricity to some experiments, a data connector to the Alpha Imaging Spectrometer, insulation on the Japanese robotic arm, and a shield cover on Pressurized Mating Adapter 3. In total, there have been almost 1248 hours of spacewalks since the first one in 1998.

For more information on station activities, go to: https://www.nasa.gov/mission_pages/station/main/index.html .

Sunday, May 7, 2017

Surprise! Military shuttle X-37B lands at KSC

Front view of the X-37B on the shuttle runway at the Kennedy Space Center. Engineers wear protective suits so they will avoid contamination by any volatile chemicals. (US Air Force photo from Spaceflightnow.com)

The fourth X-37B mission has finally come to an end. Currently the US Air Force has two X-37 spacecraft (that we know of), and this was spacecraft number - well, we don't know, because the US Air Force does not officially disclose which of its spacecraft are up there during a mission. We DO know that it lifted off on May 20, 2015, on an Atlas 5 booster from Cape Canaveral LC-41. It spent 718 days in space.
 
 Side view of the X-37B. (US Air Force photo from Spaceflightnow.com)

For more information on this mission, check out SpaceFlightNow.com:
https://spaceflightnow.com/2017/05/07/x-37b-spaceplane-returns-to-earth-and-makes-precision-autopilot-landing/

50 Years Ago: Surveyor 3 on the Moon

Photo of Surveyor 3 actually on the Moon, as taken by astronauts of Apollo 12 years later.

Fifty years ago, NASA continued its preparations for the Apollo program by landing another probe on the lunar surface. This was the third in the Surveyor series, built by Hughes Aircraft, and principally tasked with getting photos of the surface, and sampling the soil. This was the first space probe to include an extendable scoop to bring lunar dust to a sampling experiment on the lander. Surveyor 3 lifted off from Cape Kennedy from launch complex LC-36B on April 17. 

An Atlas-Centaur booster used to place the Surveyor spacecraft on the Moon. This is the one from Surveyor-1. 

Surveyor 3 touched down on April 20, 1967, in the Mare Cognitum part of Oceanus Procellarum. It had a hard landing because the descent radar incorrectly calculated the altitude and shut the engine down early. It then bounced several times, as high as 10-meters on one bounce, eventually soft-landing and staying upright. Over the short time of its mission it took over 6,000 images to send to excited scientists on Earth.


One of the panorama-series of images taken by Surveyor 3.
 
The sampling arm on the spaceprobe made four short trenches in the soil. Each scoop would bring the sample up to a camera that would then take close pictures of the soil appearance and then transmit the images back to Earth.
Surveyor 3 is the most famous of the seven Surveyor missions, because of what happened during the Apollo 12 mission in 1969. Astronauts from Apollo 12 landed very close to the spacecraft (on purpose!) and retrieved several pieces for return to Earth and analysis. 
 

The camera from Surveyor 3, currently on display at the Smithsonian National Air and Space Center in Washington, D.C.

Saturday, April 29, 2017

China succeeds at first resupply spacecraft docking

Engineers helping to assemble the Tianzhou-1 robotic space cargo vessel.
 
On Thursday April 19, China took another step toward its goal of permanent Chinese presence in Earth Orbit, with the launch of a Long March 7 from the Wenchang Space Launch Center. Atop the rocket as the Tianzhou-1, China's first robotic resupply spacecraft. Looking very similar to the standard shape of international space cargo ships such as Cygnus, Japan's H-2, ESA's ATV, the Tianzhou-1 was set on an orbital approach to rendezvous with the Tiangong-2 space station.
Computer representation of Tianzhou-1 in orbit with power panels deployed.
 
Computer representation of Tianzhou-1 docking with the station Tiandong-2.
 
 The spacecraft rendezvoused with the station and docked successfully on Saturday the 22nd. With the main objective completed, engineers will study the combined craft operations and testing for two months. After that, Tianzhou-1 will undock and then begin a three-month period of orbital testing. Like many other cargo spacecraft, Tianzhou-1 is not designed to safely land back on Earth, but will eventually be de-orbited and burned up in the atmospheric re-entry.